** Applications of Flexible Electronics**

**R. N. Ingle Principal**

**3. Solution of the field equations**

**3.2 The physical parameters of the model**

The physical parameters expansion scalar

### ^{}

and shear scalar ### ^{}

of model (36) are given by
*t*

### 1

###

(43)2

2

### 3 1

### 3

### 1

*t*

###

*m*(44)

**Conclusion : **

In this paper, we have investigated inhomogeneous cosmological model with bulk viscous fluid and
time dependent cosmological term -by using a simple power function of energy density (*t*)_{0}^{n}, where

0and *n* are constant in scalar tensor theory of relativity. The value of parameters can be obtained by using
explicit solutions of the field equations. The cosmological term is a decreasing function of time and this
approaches a small value as time increases. It is observed that at*t*0, the involved parameters in both physical
and kinematical of the models diverges while the parameters remain finite and well behaved for *t*0.

**References**

[1]R.C.Tolman . , Proc. Nat. Acad. Sci** 20, **169 (1934).

[2] H. Bondi. ;, Mon. Not. R. Astro. Soc** 107**, 410 (1947).

[3]A.H.Taub, Ann. Math. **53**, 472 (1951); ,A.H.Taub, Phy. Rev.**103**, 454 (1956).

[4]N.Tomimura, II Nuovo Cimento B **44**, 372 (1978).

[5] P.Szekeres,; Commun. Math. Phys, **41,** 55 (1975).

[6]C.B. Collins,D.A. Szafron ; J. Math. Phy. **20**, 2347 (1979).

[7]A. Pradhan ,A. Raj,S.K.Singh,; Astrophys. Space Sci. **312**,261 (2007).

[8]Y.K.Lau : Astrolian, Journal Physics, **38**, 4, 547-553(1985).

[9]M. Dersarkissian,; Nue, Cim, **B 88**, 29(1985).

[10] B. Ratra and P.J.E. Peebels, : Phys, Rev, **D 37**, 3406 (1998).

[11] V.Sahini and A. Starobinsky:, Int,J. Mod, Phys **D-9**, 373 ; gr-qc/9904398 (2000).

[12] P.J.E.Peebles and B.Ratra,; Rev. Mod. Phys., Vol. **75**,559 (2003).

[13] J.P.Sing, A. Pradhan and A.K. Singh,; Astrophys, Space Sci, **314**, 83-88 (2008).

[14]G.P. Sing and A.Y. Kale, ; Int, J. Theor, Phys, **48** 1177-1185(2009).

[15]M.K.Verma. and Shri Ram ; Int, J. Theor, Phys **49**, 693-700 (2010).

[16] M.K.Verma and Shri Ram ; Adv. Studies Theor, Phys, **5**, 8, 387-398 (20110).

[17] A. Pradhan, and S. Lata, ; Elect. J. Theor. Phys.,**vol.8,** no, 25, pp. 153-168 (2011).

[18] A.Pradhan, L.S.Yadav and L.T.Yadav,; ARDN journal of Science and Technology **3**,4,422-429
(2013).

[19] S.Weinberg,; Astrophys, J. **168**, 175 (1971).

[20] M.Heller and Z. Klimek,; Astrophys, space Sci, 53, 37 (1975).

[21] C.W.Misner,; Nature **214**, 40 (1967).

[22]C.W.Misner,; Astrophys, J, **151,** 431 (1968).

[23] C.B.Collins, J.M. Stewart,; mon Not R Astron, soc **153**, 419 (1971).

[24] Wang Xing Xiang.,; Astrophys, Space Sci** XXX**, 1-8(2004).

[25] Brans,C.H.,Dicke,R.H.,:1961Phys,Rev.**124**,925.

[26] Nordtvedt, K., :1970, Post-Newtonian Metric for a General Class of Scalar-Tensor Gravitational
Theories and Observational Consequences, Ap. J.,**161**,1059.

[27] Saez D., Ballester,V.J.:1985, Phys. Lett. **A113**, 467.

[28]R.Bali and S. Dave; Pramana J. Phys **56**, 513 (2001).

[29] K.S.Adhav,A.S. Nimkar,M.R. Ugale, V.B. Raut,;Fizilea B :2009 **18**,2,55-60 (2001).

[30] M.K.Verma and Shri Ram ; Applied Mathematics **2**, 348-354 (2011).

[31]Mete, V.G. et al.; Int, J. Theor, Phys, **54 **Issu.7 (2015).

[32] R.C.Sahu ,; Res.Astron. Astro. phys. **10** No. 7, 663-671, (2010)
[33]D. Pavon, J. Bafaluyand D.Jou,; Class. Quant. Grav. **8**, 357 (1991).

[34]R.Maartens,; Class Quantum Gravit. **12**, 1455 (1995).

[35]W. Zimdahl,; Phys, Rev, D **53**, 5483 (1996).

[36]S.Weinberg,; Gravitation and Cosmology, Wiley, New York(1972).

[37]N.O.Santos,R.S. Dias and A. Banerjee, ; J. Math. Phys. **26**, 878 (1985).

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**Axially Symmetric Perfect Fluid Cosmological **
**Model In Modified Theory Of Gravity **

**V P Kadam * , **

*Dept of Math, Gopikabai Sitaram Gawande College , Umarkhed- 445206, India

**Abstract: **

*With an appropriate choice of the function* *f*(*R*,*T*)_{, }*an anisotropic Axially Symmetricspace – time filled with *
*perfect fluid in general relativity and also in the framework of * *f*(*R*,*T*) *gravity proposed by Harko et. al. (in *
*arXiv:1104.2669[gr-qc],2011) has been studied. The field equations have been solved by using the anisotropy features of *
*the universe in Axially Symmetricspace – time. We have been discussed some physical properties of the models. We *
*observed that the involvement of new function* *f*(*R*,*T*)*does not affect the geometry of the space-time but slightly changes *
*the matter distribution. *

**Keywords:***f*(*R*,*T*)*gravity, Perfect Fluid,Axially SymmetricUniverse, General Relativity. *

**1.Introduction: **

Cosmological observations on expansion history of the universe indicate that current universe is not only expanding but also accelerating. This late time accelerated expansion of the universe has been confirmed by high red-shift supernovae experiments. Also, observations such as cosmic background radiation and large scale structure provide an indirect evidence for late time accelerated expansion of the universe.

Recently several modified theories of gravity have been developed and studied, in the view of the late
time acceleration of the Universe and the existence of dark energy and dark matter. Noteworthy amongst them
are the *f*(*R*,*T*) theory of gravity proposed by Nojiri and Odintsov (2003a) and *f*(*R*,*T*) theory of gravity
formulated by Harko et al. (2011). Bertolami et al. (2007) proposed a generalization of *f*(*R*) theory of gravity
by including in the theory an explicit coupling of an arbitrary function of the Ricci scalar R with the matter
Lagrangian density *L*_{m}. Nojiri and Odintsov developed a general solution for the modified *f*(*R*) gravity
reconstruction from any realistic FRW Cosmology. They have showed that modified *f*(*R*) gravity indeed
represents a realistic alternative to general relativity, being more consistent in dark epoch. Nojiri et al.

developed a general program for the unification of matter-dominated era with acceleration epoch for scalar-
tensor theory or dark fluid. Shamir proposed a physically viable *f*(*R*) gravity model, which showed the
unification of early time inflation and late time acceleration.

Harko et al.(2011) developed *f*(*R*,*T*)modified theory of gravity, where the gravitational Lagrangian
is given by an arbitrary function of the Ricci scalar *R* and the trace *T* of the energy-momentum tensor. It is to
be noted that the dependence of T may be induced by exotic imperfect fluid or quantum effects. They have
obtained the gravitational field equations in the metric formalism, as well as, the equations of motion of test
particles, which follows from the covariant divergence of the stress-energy tensor. They have derived some
particular models corresponding to specific choices of function *f*(*R*,*T*). They have also demonstrated the
possibility of reconstruction of arbitrary FRW cosmologies by an appropriate choice of the function*f*(*R*,*T*).
In *f*(*R*,*T*) gravity, the field equations are obtained from a variational, Hilbert-Einstein type, principle.The
action principle for this modified theory *f*(*R*,*T*) gravity is given by

*f* *R* *T* *gd* *x* *L* *gd* *x*

*S* *G* ( , ) ^{4} _{m} ^{4}

16 1

###

_{ }

^{(1.1) }

Where *f*(*R*,*T*) is an arbitrary function of the Ricci scalar *R*, and *T*is the trace of stress energy
tensor of matter *T*_{ij}and *L*_{m} is the matter Lagrangian density.

We definethe stress energy tensor of matter as

*ij* *m*

*ij* *L*

*g*
*g*
*g*

*T*

### 2 ( )

,_{ij} 2*T*_{ij} *pg*_{ij} (1.2)

By varying the action principle (1.1) with respect to metric tensor, the corresponding field equations of )

,
(*R* *T*

*f* gravity are obtained as

*ij*
*T*

*ij*
*T*

*ij*

*R*
*j*
*i*
*i*
*i*
*ij*
*ij*
*ij*

*R*

*T*
*R*
*f*
*T*
*T*
*R*
*f*
*T*

*T*
*R*
*f*
*g*

*g*
*T*
*R*
*f*
*R*
*T*
*R*
*f*

) , ( )

, ( 8

) : ( ) (

) , 2 ( ) 1 , (

(1.3) Where

*R*
*T*
*R*
*f*_{R} *f*

( , )

,

*T*
*T*
*R*
*f*_{T} *f*

( , )

and

*ij* *ij*

*g*
*g* *T*

###

###

_{}

Here _{i}is the covariant derivation and *T*_{ij}is standard matter energy-momentum tensor derived from
the Lagrangian *L*_{m}.It can be observed that when*f*(*R*,*T*) *f*(*R*), then (1.3) yield the field equations of *f*(*R*)
gravity.

It is mentioned here that these field equations depend on physical nature of the matter field.Many
theoretical models corresponding to different matter contributions for *f*(*R*,*T*) gravity are possible. However,
Harko et. al.gave three classes of these models

### ) ( ) ( ) (

### ) ( ) (

### ) ( 2 )

### , (

3 2 1

2 1

*T*
*f*
*R*
*f*
*R*
*f*

*T*
*f*
*R*
*f*

*T*
*f*
*R*
*T*
*R*
*f*

Assuming,

) ( 2 )

,

(*R* *T* *R* *f* *T*

*f* _{ } (1.4)

as a first choice, where *f*(*T*) is an arbitrary function of trace of the stress energy tensor of matter
Then from (1.3) and (1.4), we get the gravitational field equation as

*ij*
*ij*

*ij*
*ij*

*ij*

*ij* *Rg* *T* *f* *T* *T* *f* *T* *f* *T* *g*

*R* 8 2 '( ) 2 '( ) ( )

2

1

###

(1.5)Wherethe overhead prime indicates differentiation with respect to the argument.

The Friedmann-Robertson-Walker models are the only globally acceptable perfect fluid space-times which are spatially homogenous and isotropic. The adequacy of isotropic cosmological models for describing the present state of the universe is no basis for expecting that they are equally suitable for describing the early stages of the evolution of the Universe. At the early stages of the evolution of Universe, it is, in general spatially homogenous and anisotropic. Bianchi spaces are useful tools for constructing spatially homogenous and anisotropic cosmological models in general relativity and scalar-tensor theories of gravitation. Reddy et. al.

(2012a, 2012b) have obtained Kaluza-Klein cosmological model in the presence of perfect fluid source and
Bianchi type *III* cosmological model in *f*(*R*,*T*)gravity using the assumption of law of variation for the
Hubble parameter proposed by Bermann (1983), Shamir et al.(2012) obtained exact solution of Bianchi type-*I*
and type-*V* cosmological model in *f*(*R*,*T*) gravity. Chaubey and Shukla (2013) have obtained a new class of
Bianchi cosmological models in *f*(*R*,*T*) gravity. Reddy and Santi Kumar (2013) have presented some
anisotropic cosmological models in this theory. Recently Rao and Neelima (2013) have discussed perfect fluid
Einstein-Rosen universe in *f*(*R*,*T*) gravity, Sahoo et al. (2014) have studied Axially symmetric cosmological
model in *f*(*R*,*T*)gravity. Pawar et al.(2014) have discussed Cosmological models filled with a perfect fluid
source in the *f*(*R*,*T*) theory ofgravity

Sharif and Zubir (2012) investigated the anisotropic behavior of perfect fluid and massless scalar field for Bianchi type-

*I*

space time in this theory. The negativeconstant deceleration parameter in presence of
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perfectfluid is studied in Bianchi type-*III* cosmological model(Reddy et al. 2012). Bianchi type-*III* dark
energy model isderived in presence of perfect fluid using special law of variationfor Hubble‟s parameter
(Reddy et al. 2013). Yadav (2013) constructed Bianchi type-*V* string cosmological model with power law
expansion in thistheory. Mishra and Sahoo (2014) solved the field equationsof Bianchi type-*VI*_{h}cosmological
model in presence of perfectfluid in *f (R,T ) *gravity. Sahoo et al. (2014) constructed an axiallysymmetric
cosmological model in *f (R,T ) *theory inthe presence of a perfect fluid source. Ahmedand Pradhan (2014)
constructed Bianchi type-*V* cosmologicalmodel for a specific choice of *f*(*R*,*T*) *f*_{1}(*R*) *f*_{2}(*T*).

In this paper, We study anisotropic Axially symmetric models with perfect fluid matter source in )

,
(*R* *T*

*f* gravity. We present the explicit field equations in *f*(*R*,*T*) gravity for Axially symmetric model in
presence of a perfect fluid for a particular choice of *f*(*R*,*T*)*R*2*f*(*T*).We obtained solution of field
equations.We discuss some properties of the cosmological model.

**2.The Metric and Field Equations: **

We consider axially symmetricspace-time given by

###

^{2}

^{2}

^{2}

###

^{2}

^{2}

2 2

2 *dt* *A* *d* *f* *d* *B* *dz*

*ds*

###

###

(2.1)

Where *A*and *B* are the functions of cosmic time

*t*

, f is function of ###

only.Since there is no unique definition of the matter Lagrangian ,the problem of perfect fluids described by an energy density

###

, pressure*p*and four velocity

*u*

^{i}is complicated. Therefore, here, we assume that the stress energy tensor of matter is given by

*p*
*u*

*u*
*p*

*T*_{j}^{i}

### (

### )

_{i}

^{j}

###

^{i}

_{j}(2.2)

And the matter Lagrangian can be taken as *L*_{m} *p*
and we have

### 0

_{j} _{i}

*i* *u*

*u* ,*u*^{i}*u*_{i} 1 (2.3)

The matter tensor for perfect fluid is
*p*
*T*_{j}^{i} ^{i}_{j}

*i*

*j*

###

### 2

(2.4)The field equations in *f*(*R*,*T*) theory of gravity for the function *f*(*R*,*T*)*R*2*f*(*T*)
When the matter source is perfect fluid are given by

*R*
*R*

*G*^{i}_{j} ^{i}_{j} ^{i}_{j}
2

1

###

^{i}

_{j}

*i*
*j*
*i*

*j* *f* *T* *T* *pf* *T* *f* *T*

*T*

###

### 2 ' ( ) 2 ' ( ) ( )

### 8

(2.5)

where the prime indicates the derivative with respect to the argument.

Now, choose the function *f*(*T*)as the trace of the stress energy tensor of the matter so that
*T*

*T*

*f*( ) (2.6)

Where

###

is a constant.Using commoving coordinate system, the field equations for the metric (2.1) with the help of (2.4) to (2.6) can be written as

*p*

*B*
*B*
*A*
*A*
*B*
*B*
*A*

*A*^{44} ^{44} ^{4} ^{4} (8 3 )

(2.7)

*p*

*f*
*A*

*f*
*A*

*A*
*A*

*A* (8 3 )

2 _{2}^{11}

2 4

44 (2.8)

*f* *p*
*A*

*f*
*B*
*B*
*A*
*A*
*A*

*A*

2 ^{4} ^{4} _{2}^{11} (8 3 )

2 4

(2.9)

where the suffixes 1 and 4 after an unknown functions denote partial differentiation with respect to and

*t*

respectively.

The functional dependence of the metric together with (2.8) and (2.9) imply that

2,

11 *k*

*f*

*f* *k*^{2}*cons*tan*t* (2.10)
If

*k* 0

then *f*()

*c*

_{1}

*c*

_{2}, 0.

Where *c*_{1},*c*_{2}are integrating constants. Without loss of generality by taking *c*_{1} 1and *c*_{2} 0, we get

) (

*f* resulting in the flat model of the universe (Hawking and Ellis ).

With the help of (2.10), (2.7) to (2.9) reduce to

*p*

*B*
*B*
*A*
*A*
*B*
*B*
*A*

*A*^{44} ^{44} ^{4} ^{4} (8 3 ) (2.11)

*p*

*A*
*A*
*A*

*A* (8 3 )

2

2 4

44 (2.12)

*B* *p*
*B*
*A*
*A*
*A*

*A*

2 ^{4} ^{4} (8 3 )

2 4

(2.13)

These are three linearly independent equations with four unknowns *A*,*B*, and *P*. Inorder to solve
the system completely. We assume that

*B**m*

*A* (2.14)

Equation (2.11) and (2.12) implies that,

4

### 0

4 44 2 4

44

*B*
*B*
*A*
*A*
*B*
*B*
*A*

*A*
*A*

*A* (2.15)

Using equations (2.14) and (2.15), we get

### ^{(} ^{2}

^{}

^{1} ^{)} ^{(}

^{}

^{)}

^{2}

^{}

^{1}

*m* *ct* *d* ^{m}^{m}

*A* (2.16)

### ( 2

### 1 ) (

### )

^{2}

^{1}

^{}

^{1}

*m* *ct* *d* ^{m}

*B* (2.17)

Then metric (2.1) can now be written in the form

###

^{(}

^{2}

^{2}

^{1}

^{)}

###

^{2}

^{2}

^{2}

###

^{2}

^{2}

^{1}

^{2}

2

2 *dt*

### [( 2

*m*

### 1 )

*ct*

*d*

### ]

*d*

*d*

### ( 2

*m*

### 1 ) (

*ct*

*d*

### )

*dz*

*ds* *m* *m*

*m*

###

(2.18)From equation (2.12),(2.13), (2.16) and (2.17), we obtained the pressure and density as

###

^{2}

2

### ) ( ) 1 2 ( ) 4 ( 2

### ) 2 (

*d*
*ct*
*m*

*c*
*m*
*p* *m*

###

###

^{(2.19) }

###

^{2}

2

### ) ( ) 1 2 ( ) 4 ( 2

### ) 2 (

*d*
*ct*
*m*

*C*
*m*
*m*

###

###

(2.20)respectively.

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The metric (2.18) together with (2.19) and (2.20) represents an anisotropic Axially Symmetric Bianchi type *I*
perfect fluid cosmological model in *f*(*R*,*T*) gravity.

**3.Some Physical Properties Of The Model: **

The volume element of model (2.18) is given by

### ( 2

*m*

### 1 )(

*ct*

*d*

### )

*g*

*V*

###

(3.1)The scalar expansion

###

, shear scalar and average Hubble parameter*H*are given by

### ]

### [

*ct*

*d*

*c*

###

(3.2)2 2 2

### ] [ 18

### 7

*d*

*ct*

*c*

###

(3.3)### ] [ 3

*ct*

*d*

*H*

*c*

(3.4)

The deceleration parameter *q* is given by

2

*q* _{ } (3.5)

The average anisotropy parameter*A*_{m}is given by

2 2

### ) 1 2 (

### ) 1 ( 2

*m*
*A*_{m} *m*

(3.6) The overall density parameter is given by

)2

1 2 ( ) 4 ( 2

) 2 ( 3

*m*

*m*
*m*

^{(3.7) }

**5.Conclusions: **

In this paper we have presented an anisotropic Axially Symmetric space-time filled with perfect fluid in
the framework of *f*(*R*,*T*) gravity proposed by Harko et. al.(2011) and in general relativity.The model (2.18)
has no initial singularity for positive values of m. The spatial volume increases with time.Since the mean
anisotropy parameter*A*_{m}

### 0

, the models do not approach isotropy for*n*

### 1

_{.For}

*n*

### 1

, from field equations, we can easily see that we willget only isotropic universe.As*q*20, the model decelerates. It is observed that the energy density and pressure tends to zero for large value of time t and spatial volume increases with

0.1 0.15 0.2 0.25 0.3 0.35 0.4

-1 -0.8 -0.6 -0.4 -0.2 0 0.2

Time

Pressure

for m=1 for m=2 for m=3

time. For
*c*

*t* *d* , the volume element of the model vanishes while all other parametersthe scalar expansion

###

, shear scalar and average Hubble parameter*H*diverges.It is also observed that all the physical parameters are decreasing functions of time and they approach zero for large value of t.

**References: **

1) Bermann,M.S.: Nuovo Cimento B 74,182(1983)

2) Carroll,S.M.,et al.: Phys.Rev.D, Part Fields 70,043528(2004) 3) Chaubey,R.,Shukla, A.K.:Astrophys. Space Sci.343,415(2013)

4) Harko, T.,Lobo,F.S.N.,Nojiri,S.,Odintsov,S.D.:(2011),arXiv:1104,2669[gr-qc]

5) Nojiri,S.,Odintsov,S.D.:arXiv:hep-th/0307288(2003a)
**6**) Nojiri,S.,Odintsov,S.D.: Phys.Lett.B 562,147.(2003b)
7) Nojiri,S.,Odintsov,S.D.: Phys.Rev.D 68.(2003c)

8) Reddy,D.R.K.,Santi Kumar.R.: Astrophys. Space Sci.344,253(2013) 9) Rao,V.U.M.,Neelima,D.:Eur.Phys.J.Plus (2013)

10) Reddy, D.R.K.,Naidu,R.L.,Satyanarayana,B.:Int.J.Theor.Phys.51,3222(2012a) 11) Reddy, D.R.K., Santi Kumar.R., Naidu,R.L.: Astrophys. Space Sci.342,249 (2012b) 12) Rao,V.U.M.,Neelima,D.: Astrophys. Space Sci.345,427(2013)

13) Shamir,M.F., Jhangeer,A. and Bhatti A.A.:arXiv:1207.0708v1[gr-qc](2012) 14) Bertolami, O. et al.:Phys. Rev. D 75,104016(2007)

15) Nojiri,S.,Odintsov,S.D.: Phys.Rev.D 74,086.(2006)

16) Sahoo, P.K., Mishra, B and Reddy, G. C: Eur. Phys. J. Plus (2014) 129: 49

17) Pawar,D. D., Solanke, Y.S. : Turkish Journal of Physics (2014) doi:10.3906/_z-1404-1 18) Sharif, M., Zubir, M.: J. Phys. Soc. Jpn. 81, 114005 (2012

19) Reddy, D.R.K., Santikumar, R., Naidu, R.L.: Astrophys. Space Sci. 342, 249 (2012) 20) Reddy, D.R.K., Santikumar, R., Pradeep Kumar, T.V.: Int. J. Theor.Phys. 52, 239 (2013) 21) Yadav, A.K.: (2013). arXiv:1311.5885v1

22) Sahoo, P.K., Mishra, B.: Can. J. Phys. 92, 1062 (2014) 23) Ahmed, N., Pradhan, A.: Int. J. Theor. Phys. 53, 289 (2014)

24)Hawking, S.W.; Ellis, G.F.R.( 1976):Cambridge University Press, London

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**Structural And Optical Properties Of Nanostructured Manganesedisulphidethin **
**Film Grown By SILAR Method **

**M. R. Belkhedkar**^{1}***, Mohd. Razique**^{1}**, R. V. Salodkar**^{1}**, S. B. Sawarkar**^{1}**,A. U. Ubale**^{2}

*1*Department of Physics,
Shri Shivaji College of Arts, Commerce and Science,
Akola 444003, Maharashtra, India

2Nanostructured Thin Film Materials Laboratory, Department of Physics, Govt. Vidarbha Institute of Science and Humanities, VMV Road, Amravati 444604, Maharashtra, India

**Abstract **

*Nanostructured manganese disulphide thin film has been grown by successive ionic layer adsorption and reaction *
*(SILAR) method onto glass substrate using MnCl*_{2}*.4H*_{2}*O and Na*_{2}*S as cationic and anionic precursors. X-ray diffraction *
*study confirms the polycrystalline cubic structure of manganese sulphide [MnS*_{2}*] with average crystallite size 94 nm. *

*However, field emission scanning electron microscopy reveals porous nanocrystalline nature of manganese sulphide with *
*diffused grain boundaries.The direct optical band gap energy of manganese sulphide thin film is found to be 2.90eV. *

**Keywords:** Nanostructure; Thin films; X-ray diffraction; optical properties **1. ** **Introduction **

Since past few decades, transition metal disulphide thin films having pyrite structures such as FeS2,
CoS2, NiS2, MnS2, MoS2, WS2 plays very important role in the fields of science and technology due to its
interesting physical and chemical properties[1-5]. Amongst them manganese disulphide (MnS2) thin films have
attracted the recent researchers due its prominent applications in various fields such as supercapacitor, energy
storage devices, magnetic material, magnetic resonance imaging, cancer treatment, photocatalyst and
antibacterial activity etc. [5-7]. Manganese disulphide is a magnetic semiconducting material having cubic
pyrite structure. It exists with two forms, β-MnS2 (sphalerite type) and γ-MnS2 (wurtzite type) and undergoes
paramagnetic to antiferromagnetic phase transition near 48K. Manganese disulphide exhibits p-type
semiconducting nature with band gap energy ranges from 2.9 to 3.7 eV [7-8]. The manganese disulphide thin
film shows electrical resistivity of the order of 10^{6}–10^{7} Ω cm [8]. Recently, various methods have been used to
deposit manganese disulphide thin films such as hydrothermal method [3], successive ionic layer adsorption
and reaction [8], chemical bath deposition [9], physical vapor deposition [10] etc. Since very few reported the
deposition of MnS2 thin films by chemical methods, an attempt has been made in the present work to deposit
nanostructured MnS2 thin film by successive ionic layer adsorption and reaction (SILAR) method. SILAR
method is simple, easy to handle, non-hazardous and ecofriendly in nature. In SILAR, deposition of thin film
onto the substrate has been takes place sequentially by means of four steps such as adsorption, rinsing (I),
reaction and rinsing (II). In the present study, structural and optical properties of manganese disulphide thin
film have been studied by X-ray diffraction Field Emission Scanning Electron Microscopy, Energy dispersive
X-ray analysis and UV-Visible spectra.